Commit Graph

120 Commits

Author SHA1 Message Date
Sergey Biryukov 5c663524c2 Docs: In various `@return` tags, list the expected type first, instead of `false`.
Follow-up to [46696], [47060], [49926], [49927], [49929].

See #51800.
Built from https://develop.svn.wordpress.org/trunk@49963


git-svn-id: http://core.svn.wordpress.org/trunk@49664 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2021-01-15 20:08:07 +00:00
Sergey Biryukov 37662df05e Docs: In various `@return` tags, list the expected type first, instead of `false` or `WP_Error`.
Follow-up to [46696], [47060], [49926], [49927].

See #51800.
Built from https://develop.svn.wordpress.org/trunk@49929


git-svn-id: http://core.svn.wordpress.org/trunk@49628 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2021-01-04 17:18:04 +00:00
John Blackbourn dfe1f9b322 Docs: Promote many `bool` types to `true` or `false` where only that value is used.
See #51800

Built from https://develop.svn.wordpress.org/trunk@49927


git-svn-id: http://core.svn.wordpress.org/trunk@49626 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2021-01-03 22:04:04 +00:00
John Blackbourn 1aafbf6c6f Cron API: Improve the inline documentation for the args passed to the cron event scheduling functions.
Props chadreitsma, peterwilsoncc

Fixes #51605

Built from https://develop.svn.wordpress.org/trunk@49357


git-svn-id: http://core.svn.wordpress.org/trunk@49117 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-10-28 18:37:07 +00:00
Sergey Biryukov 1f85e7484f Docs: Consistently use third-person singular verbs for various filter descriptions, per the documentation standards.
See #50768.
Built from https://develop.svn.wordpress.org/trunk@48782


git-svn-id: http://core.svn.wordpress.org/trunk@48544 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-08-11 00:34:08 +00:00
John Blackbourn 9bc7d0a776 Docs: Another pass at some inline docs fixes mostly made by PHPCBF.
See #49572, #50744
Built from https://develop.svn.wordpress.org/trunk@48590


git-svn-id: http://core.svn.wordpress.org/trunk@48352 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-07-23 21:11:05 +00:00
desrosj 27485fd7aa General: Continuing to work towards a passing PHP Compatibility scan.
This is a final pass to fix PHP compatibiilty issues in the codebase with code changes or adding `phpcs:ignore` comments.

With this change, all PHP compatibility warnings and errors without specific tickets have been addressed (see #49810 and #41750).

Props desrosj, johnbillion, jrf.
See #49922.
Built from https://develop.svn.wordpress.org/trunk@47902


git-svn-id: http://core.svn.wordpress.org/trunk@47676 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-06-03 17:40:12 +00:00
John Blackbourn 717f0d0a3e Docs: Misc docblock corrections and improvements.
See #49572
Built from https://develop.svn.wordpress.org/trunk@47754


git-svn-id: http://core.svn.wordpress.org/trunk@47530 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-05-03 19:38:08 +00:00
Sergey Biryukov 47ed56f38f Code Modernization: Replace `dirname( __FILE__ )` calls with `__DIR__` magic constant.
This avoids the performance overhead of the function call every time `dirname( __FILE__ )` was used instead of `__DIR__`.

This commit also includes:

* Removing unnecessary parentheses from `include`/`require` statements. These are language constructs, not function calls.
* Replacing `include` statements for several files with `require_once`, for consistency:
 * `wp-admin/admin-header.php`
 * `wp-admin/admin-footer.php`
 * `wp-includes/version.php`

Props ayeshrajans, desrosj, valentinbora, jrf, joostdevalk, netweb.
Fixes #48082.
Built from https://develop.svn.wordpress.org/trunk@47198


git-svn-id: http://core.svn.wordpress.org/trunk@46998 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-02-06 06:33:11 +00:00
Sergey Biryukov 001ffe81fb Docs: Improve inline comments per the documentation standards.
Includes minor code layout fixes for better readability.

See #48303.
Built from https://develop.svn.wordpress.org/trunk@47122


git-svn-id: http://core.svn.wordpress.org/trunk@46922 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-01-29 00:45:18 +00:00
Sergey Biryukov 2900bb8ea7 Docs: Update links to https://secure.php.net/, they now redirect to https://www.php.net/.
See #48303.
Built from https://develop.svn.wordpress.org/trunk@47088


git-svn-id: http://core.svn.wordpress.org/trunk@46888 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-01-20 03:14:06 +00:00
Sergey Biryukov 4a9c0e35e1 Cron API: Use `WEEK_IN_SECONDS` constant for the `weekly` schedule added in [47062].
Props afercia.
See #47606.
Built from https://develop.svn.wordpress.org/trunk@47068


git-svn-id: http://core.svn.wordpress.org/trunk@46868 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-01-13 17:05:07 +00:00
Sergey Biryukov 26ce3c9f19 Cron API: Add a new cron schedule for `weekly` events.
Props Clorith.
See #47606.
Built from https://develop.svn.wordpress.org/trunk@47062


git-svn-id: http://core.svn.wordpress.org/trunk@46862 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-01-12 11:20:04 +00:00
Sergey Biryukov dd4d98a368 Docs: In various `@return` tags, list the expected type first, instead of `false`.
Follow-up to [46696].

See #48303.
Built from https://develop.svn.wordpress.org/trunk@47060


git-svn-id: http://core.svn.wordpress.org/trunk@46860 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2020-01-11 18:32:05 +00:00
John Blackbourn e36d1bcbd8 Docs: Docblock corrections and improvements, mostly related to various `pre_*` filters.
See #47110

Built from https://develop.svn.wordpress.org/trunk@46232


git-svn-id: http://core.svn.wordpress.org/trunk@46044 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-09-21 17:41:57 +00:00
Sergey Biryukov 8e85299a00 General: First pass at replacing Codex URLs with a corresponding HelpHub or DevHub article.
Props ianbelanger, tobifjellner, SergeyBiryukov.
See #47771.
Built from https://develop.svn.wordpress.org/trunk@45674


git-svn-id: http://core.svn.wordpress.org/trunk@45485 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-07-25 22:45:57 +00:00
Gary Pendergast abcbee954f Coding Standards: Fix instances of `WordPress.PHP.NoSilencedErrors.Discouraged`.
Noteable changes:
- The `magic_quotes_runtime` and `magic_quotes_sybase` settings were removed in PHP 5.4, so no longer need to be set.
- Some functions that use external libraries can generate errors that can't be tested for, so are globally allowed to silence errors.
- Quite a few functions would cause errors if `safe_mode` was set. This setting was removed in PHP 5.4.
- Only a handful of `header()` calls needed corresponding `headers_sent()` checks for unit tests to pass, but more may need to be added as the nightlies builds are tested.

See #46732.

Built from https://develop.svn.wordpress.org/trunk@45611


git-svn-id: http://core.svn.wordpress.org/trunk@45422 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-07-09 05:45:58 +00:00
Peter Wilson fff2440ba5 Cron: Ensure identical single events aren't scheduled less than 10min apart.
Improves the logic in `wp_schedule_single_event()` to ensure an identical event is not scheduled within ten minutes.

This moves the logic for checking for identical events to be self contained rather than relying on `wp_next_scheduled()` as this fails to account for events with a past timestamp when wp-cron fails to trigger or for multiple identical events being scheduled already.

Props bodohugobarwich.
Fixes #44818.


Built from https://develop.svn.wordpress.org/trunk@44917


git-svn-id: http://core.svn.wordpress.org/trunk@44748 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-03-16 06:42:50 +00:00
Peter Wilson 2a19ad39db Docs: Correct documentation for the `schedule_event` filter.
The filter runs for both recurring and single events.

See #42505.

Built from https://develop.svn.wordpress.org/trunk@44694


git-svn-id: http://core.svn.wordpress.org/trunk@44525 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-01-23 23:23:52 +00:00
Peter Wilson 6f337d1195 Cron: Move logic for finding the next event's timestamp.
Moves the logic for determining when an event will next run from `wp_next_scheduled()` to `wp_get_scheduled_event()`.

This improves the performance of `wp_get_scheduled_event()` by avoiding duplicate function calls and object cache hits.

Props peterwilsoncc.
Fixes #45976.

Built from https://develop.svn.wordpress.org/trunk@44693


git-svn-id: http://core.svn.wordpress.org/trunk@44524 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-01-23 23:08:51 +00:00
Peter Wilson bf3c97de77 Cron API: Add function and filter to return ready cron jobs.
Add the function `wp_get_ready_cron_jobs()` to return a modified version of the cron array limited to jobs ready to be run, ie with a timestamp of `time()` or earlier.

The new function includes the filter `pre_get_ready_cron_jobs` to allow for custom cron storage systems. This rounds out the functionality added in #32656.

Props Pento for code review.
Fixes #45797.


Built from https://develop.svn.wordpress.org/trunk@44483


git-svn-id: http://core.svn.wordpress.org/trunk@44314 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2019-01-08 21:49:49 +00:00
Peter Wilson b1c340ef5d Docs: Correct inline documentation versions for Cron API changes.
[43540] introduced changes to allow hijacking the cron implementation.

These changes were slated for 5.0, but have since been moved to the 5.1 release.

See #43540.


Built from https://develop.svn.wordpress.org/trunk@44375


git-svn-id: http://core.svn.wordpress.org/trunk@44205 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-12-30 05:06:48 +00:00
Peter Wilson 4ae9b553c5 Docs: Correct `@see` syntax for Cron API changes.
Fixes documentation errors introduced in  [43540], [43050] and [43608].

Props coffee2code.
Fixes #45445.


Built from https://develop.svn.wordpress.org/trunk@44374


git-svn-id: http://core.svn.wordpress.org/trunk@44204 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-12-30 04:51:51 +00:00
desrosj eef048a3e8 Docs: Correct inline documentation versions.
[43050] updated the Cron API to return values indicating success or failure when called.

At the time, these changes were slated for 5.0, but have since been moved to the 5.1 release. This updates the inline documentation to reflect that.

Fixes #21072.
Built from https://develop.svn.wordpress.org/trunk@44324


git-svn-id: http://core.svn.wordpress.org/trunk@44154 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-12-19 03:41:49 +00:00
Peter Wilson 51a9a80da2 Cron API: Clarify documentation for `wp_reschedule_event()`.
Expands documentation to indicate `wp_schedule_event()` ought to be used for rescheduling an upcoming event, while `wp_reschedule_event()` is used for internally rescheduling a recurring event after it runs.

Props Dharm1025, jrf.
Fixes #35968.


Built from https://develop.svn.wordpress.org/trunk@43608


git-svn-id: http://core.svn.wordpress.org/trunk@43437 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-09-03 04:04:25 +00:00
Gary Pendergast 56c162fbc9 Coding Standards: Upgrade WPCS to 1.0.0
WPCS 1.0.0 includes a bunch of new auto-fixers, which drops the number of coding standards issues across WordPress significantly. Prior to running the auto-fixers, there were 15,312 issues detected. With this commit, we now drop to 4,769 issues.

This change includes three notable additions:
- Multiline function calls must now put each parameter on a new line.
- Auto-formatting files is now part of the `grunt precommit` script. 
- Auto-fixable coding standards issues will now cause Travis failures.

Fixes #44600.


Built from https://develop.svn.wordpress.org/trunk@43571


git-svn-id: http://core.svn.wordpress.org/trunk@43400 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-08-17 01:51:36 +00:00
Peter Wilson 90f1ac17ec Cron: Add hooks and a function to allow hijacking cron implementation.
This allows sites with a large cron option or a custom cron implementation to hijack the cron option to store cron data using custom functionality.

`wp_get_scheduled_event()` is new function to retrieve the event object for a given event based on the hook name, arguments and timestamp. If no timestamp is specified the next occurence is returned.

Preflight filters are added to all functions that read from or modify the cron option: `pre_schedule_event`, `pre_reschedule_event`, `pre_unschedule_event`, `pre_clear_scheduled_hook`, `pre_unschedule_hook`, `pre_get_scheduled_event` and `pre_next_scheduled`.

Additionally, the post scheduling hooks `next_scheduled` and `get_schedule` to allow plugins to modify an event after retrieving it from WordPress.

Props rmccue, DavidAnderson, ethitter, peterwilsoncc.
Fixes #32656.


Built from https://develop.svn.wordpress.org/trunk@43540


git-svn-id: http://core.svn.wordpress.org/trunk@43369 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-07-27 02:23:25 +00:00
Peter Wilson 2e43234f3f Cron API: Return meaningful values from cron functions.
Return values added to Cron API functions to indicate outcome:

* `wp_schedule_single_event()`, `wp_schedule_event()`, `wp_reschedule_event()` and `wp_unschedule_event()`: boolean indicating success or failure,
* `wp_clear_scheduled_hook()`: integer indicating number of jobs cleared (zero or more), `false` if one or more jobs fail to clear,
* `wp_unschedule_hook()`: integer indicating number of jobs cleared (zero or more), `false` if the jobs fail to clear,
* `spawn_cron()`: boolean indicating whether job spawned,
* `wp_cron()`: integer indicating number of jobs spawned (zero or more), `false` if one or more jobs fail to spawned,
* `_set_cron_array()`: boolean outcome of `update_option()`.

Props evansolomon, jrf, peterwilsoncc, pento for code review.
Fixes #21072.


Built from https://develop.svn.wordpress.org/trunk@43050


git-svn-id: http://core.svn.wordpress.org/trunk@42879 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2018-05-01 02:05:23 +00:00
Gary Pendergast aaf99e6913 Code is Poetry.
WordPress' code just... wasn't.
This is now dealt with.

Props jrf, pento, netweb, GaryJ, jdgrimes, westonruter, Greg Sherwood from PHPCS, and everyone who's ever contributed to WPCS and PHPCS.
Fixes #41057.


Built from https://develop.svn.wordpress.org/trunk@42343


git-svn-id: http://core.svn.wordpress.org/trunk@42172 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2017-11-30 23:11:00 +00:00
John Blackbourn 850532fb01 Cron API: Improvements to docblocks for the event scheduling functions.
See #42505

Built from https://develop.svn.wordpress.org/trunk@42216


git-svn-id: http://core.svn.wordpress.org/trunk@42045 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2017-11-22 15:16:47 +00:00
Drew Jaynes b13aa27cf4 Docs: Use third-person singular verbs in the summaries for `wp_unschedule_hook()` and `wp_clear_scheduled_hook()`.
See #41017.

Built from https://develop.svn.wordpress.org/trunk@40970


git-svn-id: http://core.svn.wordpress.org/trunk@40820 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2017-06-30 04:54:41 +00:00
Sergey Biryukov 641a4b643f Cron API: Introduce `wp_unschedule_hook()` to clear all events attached to a hook.
This complements `wp_clear_scheduled_hook()`, which only clears events attached with specific arguments.

Props arena, mordauk, jrf.
Fixes #18997.
Built from https://develop.svn.wordpress.org/trunk@40965


git-svn-id: http://core.svn.wordpress.org/trunk@40815 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2017-06-30 00:22:44 +00:00
Scott Taylor 76926fa763 Cron: clarify descriptions for Cron API functions.
Props johnbillion.
Fixes #37769.

Built from https://develop.svn.wordpress.org/trunk@38357


git-svn-id: http://core.svn.wordpress.org/trunk@38298 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-08-26 09:22:30 +00:00
Sergey Biryukov 18601e4b5a Docs: In `wp_schedule_single_event()`, add a note about scheduling an event to occur within 10 minutes of another event with the same action hook.
Props medariox.
Fixes #37455.
Built from https://develop.svn.wordpress.org/trunk@38148


git-svn-id: http://core.svn.wordpress.org/trunk@38089 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-07-25 12:23:30 +00:00
Sergey Biryukov 139387b7e5 Docs: Use 3-digit, x.x.x-style semantic versioning for `_doing_it_wrong()`, `_deprecated_function()`, `_deprecated_argument()`, and `_deprecated_file()` throughout core.
Props metodiew.
Fixes #36495.
Built from https://develop.svn.wordpress.org/trunk@37985


git-svn-id: http://core.svn.wordpress.org/trunk@37926 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-07-06 12:40:29 +00:00
Drew Jaynes da78aeffe9 Docs: Apply inline `@see` tags to hooks referenced in DocBlocks in a variety of wp-includes/* files.
Applying these specially-crafted `@see` tags allows the Code Reference parser to recognize and link these elements as actions and filters.

See #36921.

Built from https://develop.svn.wordpress.org/trunk@37542


git-svn-id: http://core.svn.wordpress.org/trunk@37510 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-05-23 18:59:27 +00:00
Drew Jaynes 9cb5247392 Docs: Standardize filter docs in remaining wp-includes/* files to use third-person singular verbs per the inline documentation standards for PHP.
See #36913.

Built from https://develop.svn.wordpress.org/trunk@37518


git-svn-id: http://core.svn.wordpress.org/trunk@37486 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-05-22 18:50:28 +00:00
Drew Jaynes f52a8cb1fa Docs: Remove/replace invalid inline `@link` tags in DocBlocks in wp-includes/*.
Fixes #36910.

Built from https://develop.svn.wordpress.org/trunk@37487


git-svn-id: http://core.svn.wordpress.org/trunk@37455 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-05-22 17:39:28 +00:00
Drew Jaynes 383b9a44de Docs: Adjust formatting for an added-parameter changelog entry in the hook doc for the `cron_request` filter.
See #32246.

Built from https://develop.svn.wordpress.org/trunk@36299


git-svn-id: http://core.svn.wordpress.org/trunk@36266 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-01-14 17:30:28 +00:00
Eric Lewis 7733ed2ddc Cron: Add the cron lock timestamp to the 'cron_request' filter arguments.
Fixes #31307

Built from https://develop.svn.wordpress.org/trunk@36228


git-svn-id: http://core.svn.wordpress.org/trunk@36195 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2016-01-08 23:54:26 +00:00
Drew Jaynes df0c1aa0ed Docs: Add a missing notation for the `$gmt_time` parameter in the DocBlock for `spawn_cron()`.
See #32246.

Built from https://develop.svn.wordpress.org/trunk@36022


git-svn-id: http://core.svn.wordpress.org/trunk@35987 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-12-19 08:20:27 +00:00
Scott Taylor 2f167faeb2 Cron: In `spawn_cron()`, when using `ALTERNATE_WP_CRON`, return early for any non-`GET`, instead of naively checking `! empty( $_POST )`.
Props johnbillion, markoheijnen.
Fixes #27447.

Built from https://develop.svn.wordpress.org/trunk@34576


git-svn-id: http://core.svn.wordpress.org/trunk@34540 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-09-26 04:51:26 +00:00
Sergey Biryukov d9b7d915c2 Document `@return` value for `wp_unschedule_event()`.
See #33475.
Built from https://develop.svn.wordpress.org/trunk@34044


git-svn-id: http://core.svn.wordpress.org/trunk@34012 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-09-11 11:35:24 +00:00
Scott Taylor c1bb5b5ce3 After [33843], update the location of some files in `This filter is documented in` docs
Props dimadin.
See #33413.

Built from https://develop.svn.wordpress.org/trunk@33954


git-svn-id: http://core.svn.wordpress.org/trunk@33923 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-09-08 22:17:26 +00:00
Dion Hulse 580ca68e26 Cron: Reject events when the provided `$timestamp` is not a valid timestamp.
Invalid timestamps were previously accepted by the scheduling functions but would never be run due to our implementation which caused the cron option to forever contain the events.
This rejects such events which most likely only occur due to developer error.

Props utkarshpatel, wonderboymusic, SergeyBiryukov.
See #33423, Fixes #33475

Built from https://develop.svn.wordpress.org/trunk@33936


git-svn-id: http://core.svn.wordpress.org/trunk@33905 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-09-07 02:39:23 +00:00
Drew Jaynes 4c37f68b79 Fix inline documentation syntax in `wp_xmlrpc_server`.
See #32246.

Built from https://develop.svn.wordpress.org/trunk@32591


git-svn-id: http://core.svn.wordpress.org/trunk@32561 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-05-25 06:25:25 +00:00
Dominik Schilling 64fc7294b6 Use HTTPS URLs for codex.wordpress.org.
see #27115.
Built from https://develop.svn.wordpress.org/trunk@32116


git-svn-id: http://core.svn.wordpress.org/trunk@32095 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2015-04-12 21:29:32 +00:00
Scott Taylor e619abda6e Improve various `@param` docs for `src/wp-includes/*`.
See #30224.

Built from https://develop.svn.wordpress.org/trunk@30681


git-svn-id: http://core.svn.wordpress.org/trunk@30671 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2014-12-01 01:34:24 +00:00
Drew Jaynes 273396fe1e Ensure inline code is markdown-escaped as such, and that code snippets in descriptions are properly indented.
Affects DocBlocks for the following core elements:
* Backtick-escapes a `<link>` tag in a parameter description for the `embed_oembed_discover` hook
* Inline code fixes in the summary and return description for `WP_List_Table::get_table_classes()`
* Removes HTML markup from the summary for `WP_List_Table::display_rows_or_placeholder()`
* Backtick-escapes a `<tr>` tag in a parameter description for `WP_Users_List_Table::single_row()`
* Converts non-DocBlocks into multi-line comments in `WP_Dependencies::do_items()`
* Removes HTML markup from the summary for the `comment_form_top` hook.
* Inline code and snippet fixes in the description for `wp_get_schedules()`

Props rarst for the initial patch.
See #30473.

Built from https://develop.svn.wordpress.org/trunk@30537


git-svn-id: http://core.svn.wordpress.org/trunk@30526 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2014-11-24 04:58:22 +00:00
Scott Taylor ea679e358e `wp_schedule_single_event()` should not prevent scheduling a future duplicate event. It should only reject an event as a duplicate if there is already a similar event scheduled within 10 minutes of the given timestamp.
Adds unit tests, fixes existing cron test.

Props tellyworth.

See [9181], #6966.
Fixes #28213.

Built from https://develop.svn.wordpress.org/trunk@29939


git-svn-id: http://core.svn.wordpress.org/trunk@29690 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2014-10-17 19:17:18 +00:00